<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body>
<style>
    /*伪类选择器，这样写整个页面的字体都变成红色，相当于document被hover了*/
    :hover{
        color: red;
    }
    p:hover{
        color: blue;
    }
</style>
    <p>11111111</p>
</body>
</html>